Principal Mechanical Design Engineer – Water Industry

Tetra Tech; Warrington; Hybrid; GBP 90,000 - 120,000; Full time

Job summary

Tetra Tech’s Water Consultancy is seeking multiple Principal Mechanical Design Engineers to lead mechanical design delivery across major UK water frameworks. You will own outputs for pumping systems, aeration and process plant equipment from optioneering through detailed design and construction support, producing specifications, P&IDs, schedules and procurement documentation.

Hybrid working with regional offices and UK-wide site visits are expected.

Qualifications

• IMechE-accredited degree or equivalent; chartered status or working towards chartership.
• Substantial water sector experience.
• Ability to lead mechanical design across pumping systems and process plant.

Responsibilities

• Lead mechanical design delivery across UK water frameworks.
• Produce specifications, P&IDs, schedules and procurement documentation.
• Coordinate multi-disciplinary teams and engage clients.
• Provide technical assurance on capital schemes.
• Support construction and site survey outputs.

Skills

Pumps & process design

Multidisciplinary coordination

Technical documentation

Regulatory compliance & safety

Client engagement & procurement

Education

IMechE accredited degree

Chartered engineer status / towards chartership

Postgraduate qualification

AMP programme experience

Tools

AutoCAD

3D CAD tools

P&ID software

Job description

Lead mechanical design for national water programmes

Purpose and scope of the role: Tetra Tech's Water Consultancy is seeking multiple Principal Mechanical Design Engineers to lead mechanical design delivery across major, long–term UK water industry frameworks. You will own mechanical design outputs for pumping systems, aeration and process plant equipment from optioneering through detailed design and construction support, producing specifications, P&IDs, schedules, calculations and procurement documentation. Projects include a GBP100 million, 10–year United Utilities framework and a broad AMP8/AMP9 portfolio. You will coordinate multi–disciplinary teams of engineers, modellers and data analysts, engage clients and supply–chain partners, and provide technical assurance on multi–million–pound capital schemes.

Your impact in this position:

In the short term you will deliver robust mechanical designs and site survey outputs. Over the medium term you will optimise plant performance, improve constructability and reduce whole–life carbon and cost across programmes. Longer term you will capture technical knowledge, develop technical leaders and influence regional delivery strategy, with clear progression into senior technical or programme leadership roles.

Core capabilities:

• Pumping and process systems design – Demonstrable experience sizing and specifying pumps, aeration systems and ancillaries with justified selection and performance calculations.
• Multidisciplinary coordination – Proven ability to integrate mechanical designs with civil, structural, electrical, process and ICA disciplines and lead technical workshops and HAZOPs.
• Technical documentation and digital skills – Proficiency producing P&IDs, GA drawings, datasheets and use of AutoCAD/3D tools or similar digital design workflows.
• Regulatory, safety and constructability awareness – Strong knowledge of CDM duties, statutory standards and designing for safe, maintainable installations.
• Commercial and client engagement – Track record managing design deliverables to time, cost and quality, advising clients and supporting procurement on NEC/ECC or similar contracts.

Skills, qualifications and experience:

Expected: IMechE–accredited degree or equivalent, chartered or working towards chartership, substantial water sector experience. Desirable: postgraduate qualification and demonstrable AMP programme experience.

Work patterns & locations:

Hybrid working with regional office attendance; typical expectation two to three days per week onsite depending on project needs. Travel to client sites and project locations across the UK will be required. Competitive salary and benefits; flexible arrangements considered in line with delivery requirements.

Why join Tetra Tech?

Tetra Tech is a leading provider of consulting and engineering services working across the full project lifecycle worldwide. We have a wide range of expertise across our teams, providing a global support network with a personalised approach to client relationships to better understand where we can add value. We provide a collaborative environment that supports individual performance, innovation, and creativity.

We support public and private sector clients on local, national, and international projects to deliver sustainable and resilient solutions. Our operations in the UK, Ireland, and the Netherlands include more than 6,000 employees who are Leading with Science to solve our clients' most complex problems.

In alignment with the Equality Act 2010, we will make reasonable adjustments to support candidates and employees requiring additional arrangements. This could include adaptations to work schedules, training approaches, or the physical workspace. Please inform us if you need any accommodations during the recruitment process or in your day–to–day role.